Polyaniline/poly (2-acrylamido-2-methyl-1-propanesulfonic acid) modified cellulose as promising material for sensors design

A material based on cellulose coated with polyaniline/poly (2-acrylamido-2-methyl-1-propanesulfonic acid) (Cell/PANI-PAMPSA) was synthesized in a simple way starting from cellulose fibres, aniline and using PAMPSA as dopant. The morphology, mechanical properties, thermal stability, and electrical conductivity were investigated by means of several complementary techniques. The obtained results highlight the excellent features of the Cell/PANI-PAMPSA composite with respect to the Cell/PANI one. Based on the promising performance of this material, novel device functions and wearable applications have been tested. We focused on its possible single use as: i) humidity sensors and ii) disposable biomedical sensors to provide immediate diagnostic services as close to the patient as possible for heart rate or respiration activity monitoring. To our knowledge, this is the first time that Cell/PANI-PAMPSA system has been used for such applications.

Mild fabrication of silica-silver nanocomposites as active platforms for environmental remediation

A new, simple and convenient approach to prepare silver nanoparticles supported on SiO₂–PEI composites for the decoloration of organic dyes.

Sterically driven synthesis of ruthenium and ruthenium–silver N-heterocyclic carbene complexes

A sterically driven synthetic route from non-bulky silver NHC to novel Ru(NHC) complexes and from bulky Ag(NHC) to unprecedented heterobimetallic Ru–Ag(NHC) complexes is presented.

Gold nanoparticles on nanodiamond for nanophotonic applications

We present here some recent results of a research focused on the preparation of detonation nanodiamond/Au nanoparticles hybrid materials. Two different experimental routes are followed for the decoration of diamond nanoparticles by Au nanoparticles, that are in turn prepared by an innovative electroless approach.

Structure and morphology at the nanoscale level of the Au-on-nanodiamond deposits have been deeply investigated by electron microscopy (FE-SEM, HR-TEM) and diffraction (XRD) techniques.

Optical properties of these systems have been determined by performing scattering and UV-Vis absorption measurements, and by comparing the experimental data with simulated extinction spectra. The results highlighted very interesting plasmonic and scattering behaviors, mainly related to the high refractive index of diamond.

RF-sputtering preparation of gold-nanoparticle-modified ITO electrodes for electrocatalytic applications

The preparation of gold-nanoparticle (AuNPs)-modified indium tin oxide (ITO) electrodes (AuNPs/ITO) was performed by radio-frequency (RF) sputtering from Ar plasmas at temperatures as low as 60 °C, tailoring the AuNP morphology and content as a function of the sole sputtering time. The latter parameter was varied from 5 to 20 min in order to investigate the influence of gold amount and distribution on the electrochemical performances of the resulting AuNPs/ITO systems. The electrodes were characterized using field emission-scanning electron microscopy (FE-SEM), UV-vis absorption and x-ray photoelectron spectroscopies (XPS); moreover variable scan rate cyclic voltammetry (CV) studies were performed to examine their electrochemical behavior. The electrocatalytic activity of the nanostructured AuNPs/ITO electrodes toward methanol oxidation was investigated and compared with a continuous gold film (Aufilm/ITO). The catalytic efficiency of the AuNPs/ITO systems was found to increase with the gold content and the AuNPs-support boundary region in the corresponding samples. For the longest sputtering time (i.e. 20 min) the performances of the nanostructured electrode were better than the Aufilm/ITO reference, despite the much lower catalyst amount. Furthermore, conversely from the AuNPs/ITO samples, in the Au(film)/ITO case the gold film displayed a poor adhesion to the substrate and the electrode could be used only for a limited number of electrochemical cycles.